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From the North Sea coasts very little information is to hand, which is in agreement 

 with the fact, that the tiny elvers are not here as on the Atlantic the object of a fishery 

 and thus receive little attention. It is known however, that the ascent does not begin on 

 the coasts of Denmark before April, and in the inner Danish waters (Kattegat, Belt Sea) 

 in general not before May. 



At the inner Danish waters and the western Baltic we come to the eastern 

 boundary for the tiny elvers (Stage 5). These have hitherto never been found in 

 the inner Baltic, neither in the sea nor in fresh water, whereas the ascent of larger eel 

 young over 20 cm. long takes place in the Baltic as far up as in the Gulf of Bothnia. 



All the facts given in the last few pages confirm the correctness of the view, that 

 the eel is not born nor do the larvae develop nearer the coasts of North Europe than in ^ 

 the Atlantic off Great Britain and France and that consequently the whole of the 

 North European stock of eels depends upon the young which migrate 

 inwards from that region. 



When the eel larvae have become elvers in the autumn out in the Atlantic it is 

 necessary for them to get into the shallow coastal waters and fresh water, to which 

 their future life up to the period of reproduction is bound. Thus, even in the beginning 

 of November the tiny elvers in Stage 5 have been found in the Atlantic on their way in 

 towards the coast of northern West Europe'. Here the most of them strike land on 

 which they can pass their lives, but a smaller number do not reach their goal so quickly 

 and thus pass through the English Channel into the North Sea, to which also some reach 

 northwards round the British Isles. 



Many of the remaining elvers succeed in getting firm "foothold" on the North Sea 

 coasts but not all, and these last then pass through the Skager Rak into the Kattegat and 

 Western Baltic. Meantime the period of the year has so far advanced, that the meta- 

 morphosis is nearing its end for the majority, and in consequence, the elvers now give 

 up the pelagic mode of life they have hitherto led and become bottom-animals before they 

 have reached into the true Baltic. That only or essentially only the older stages of the 

 young eel are found so far in is thus explained in a natural manner. 



It is consequently but an extremely small fraction of the eel fry born to the west of 

 Great Britain and France which reach so far as to the Danish waters and the Baltic, as 

 most fall out on the way ; but the distance they must overpass is nevertheless very long. 

 That it is at all possible for the fry to travel a distance of such unusual length is due 

 in the first place to the unusually long duration of the pelagic life. 



The eel is however not the only species whose young stages can occur a long way 

 from the places, where they were spawned. Many examples of this might be named 

 even amongst the important food-fishes, as for example the cod at Iceland and northern 

 Norway. What is specially remarkable about the eel is first and foremost the ability of 

 the young to live under conditions, which are as totally different from those under which 

 they are spawned as shallow fresh water is from the salt water of the depths of the 

 Atlantic. 



■ On the north coast of Spain, where the elvers of Slage 5 have practically no distance to travel from 

 the deep water to the land, the ascent may begin even in September (at Santander). 



